Film projector housing construction



1952 D. 1. CRITOPH ET AL 2,614,453

FILM PROJECTOR HOUSING CONSTRUCTION Filed Oct. 25, 1948 4 Sheets-Sheet 1 J 1 f? T K INVENTOR. 17 4/11; I. 6/?! TOPH F 0 H. VI/OLFORfl y JOHN E Hf fi/w/v/v Oct. 21, 1952 D. CRITOPH ET AL FILM PROJECTOR uousmc CONSTRUCTION Filed Oct. 23, 1948 IN VEN TOR.

CI?! TgPH ERRMAN/V Oct. 21, 1952 D. l. CRITOPH ET AL FILM PROJECTOR HOUSING CONSTRUCTION 4 Sheets-Sheet 5 Filed Oct. 25, 1948 INVENTOR. .DA VJD I. C/PITOPH M w w 0 2 M a m 0 70. 4 m s m m w 4 a 2 m Z 2 n M4 Patented Oct. 21, 19.52

STATES PATENT OFFICE Q q I 4 I FILM-PROJECTOR HOUSING 1 CONSTRUCTION David InCritoph, Snyder, and John F. Herrmanm Ch'eektowaga, N."X., and Fred H. Wolford, 7 Albuquerque, N. Mex., assignors to American Optical-Company, Southbridge, Mass., a voluntary association of Massachusetts Application October 23, 1948, Serial No. 56,222

' This invention relates "to projection apparatus.

14 Claims. (Cl. 88-26) for use with transparencies and more, particularly to certain details of constructionlrelating to mounting; positioning and providing ready access to elements of the apparatus, for dissipating heat therefrom,"'and for framing the transparen'cies.

An object oftheinventio isto provide a projector'of simpleand sturdy construction andefficient performance;

Another object projector'emb'odying improved constructions for dissipating heat generatedby'a light/source so reflected image thereof may be" performed ex-' teriorly of the :projector'housing; subsequent reinsertion of the unit in the projector and positioning thereof r ela'tiv'e j to the focal plane. of a condenser lens system being rendered possible. .A still further object of the invention is to provide a projector having "novel i nean's for mountinga condenser lens systememployed therein.

' Another object of-the invention isto-provide novel means for'framing image areas of slide films of various dimensions. 5.

A:further object of the invention isto provide novel reflector mounting means for positioning the real image of a lamp fllament relative to the latter. p j

,fl'fhese and other objects of the invention will be, apparent from the following description taken in connection with the accompanyingdrawings, wherein like =reference-characters refer to lik parts throughout the severalviews: 1

,Eigure 1 isa side view of the projector; Fig. 2 is 'aplan view oi the projector;

Fi 3 s alside vi'ew, rin projector, partly in section; V

I Fig. 4 is'a sectional planview of the-projectom;

Fig. '5 is a fragmentary rear view oi'tilting mechanism of theprojector;

QFig. 6 isa v projector including aiefleotor and a "heat baflle; isafro-nt viewof .thesubassembly shown mFigj; r.

"Fig. 8159,

side viewers condenser lens system of the invention is to provide a lan view] of a subassembly of the and means for mounting the same in the projector; a I i r Fig. 9 is a plan view of the elements shown in Fig. 8-; I

Fig. 10 is a front Figs. 8 and 9;

Fig. 11 is aside view of mechanism adapted to convert the projector into a slide film projector; Fig. 12 is a rear view of elements shown in part view of an element shown in Fig. 13 is a front view of elements shown in Figs. 11 and 12; and

.Fig. 14 is a perspective projector shown in Fig. 1.

w Referring to Fig. 1, an exteriorside view of slide and slide film projector is shown. The projector comprises a plurality of cooperatingpor tions for housing and supporting its various components. Said portions include a-base member I2 which formsa lower chamber within its walls,

said member l2 comprising alower wall I2a hav-,

ing, a plurality of supporting feet [4, formed of rubber or the like attached thereto. A plurality of apertures l6 (Fig. 3) are formed in lower wall l.2atpro viding means for intake of air to said chamber wherein a motor-driven fan is located. Toggle switch I! is employedin motor and lamp circuits of the projector. A relatively large aperture I8 is formed in an upper wall I2b of base I2 for receiving a supporting member 20. An insulating baffle 2| is provided for separating said supporting member from electrical wiring (not.

shown) leadingto toggle switch l1. Supporting member 20 is pivotally mounted upon base l2;as, for example, by a pair of bosses or protuberances 22.

porting member 20 so thatthese side wall portions may pivot thereon. sidewall portions .Zfla; extend downwardly and terminate within base member 20 inthe form of an openingleading'into the chamber ofthe latter. A split construction the lower indentations from bosses 22 sothat supporting member 20 maybe separatedirorn base "I2. Removal. of member 20 permits ready. access to-chamber means (ifbase: 12 through 'aperture'IB.

p view of strip fimi sup-- porting means which may be employed in the l5 Said'bosses are formed to extend inwardly: from the sides of base l2 and have theirjinner;.- ends positioned betweenpairs of indentations 24 2 formed in frontal sidewall portions 20o of sup- Supporting member 23 is capable of being tilted about said pivotal means 2224. Means for the purpose comprise a lever 28 (Figs. 1 and having a pivot 30 preferably rigidly fastened thereto, the latter being rotatably mounted in av portion of lever 28, is slidably positioned in an angular cam slot 36 formed in one of said side wall portions a, as shown in Fig. l, and extending from its lower extremity upwardly and forwardly at a predetermined angle. friction surfaced washers 38 and 40, preferably of a fiber composition, are mounted upon pin 34 at each side of said side wall portion 29a adjacent slot 36, and are held in frictional contact therewith by spring washer 42 and self-locking nut 44 which is threaded upon pin 34 as shown. Through adjustment of locking nut 44, correct frictional contact of washers 38 and 40 with side wall 20a may be established. Said frictional contact is preferably such that when lever-handle 28.0., which projects outwardly of base l2 through a slot or recess 45, is manually actuated the braking action of washers 38 and 40 is overcome and pin 34 is permitted to move along slot 36, thereby causing supporting-member 20 to tilt or pivot as enabled by pivotal means 2224. A correct adjustment also provides that when handle 28a is. released, said frictional contact of the washers and wall portions 20a under bias of spring washer 42 is sufficient to hold pin 34 at any given stage of its travel in slot 36 and, accordingly, sufficient to hold supporting member 20 at any angle to which it has been tilted. The angular inclination of slot 36, providing different radii along its surfaces, with respect to pivot 30,

taken in conjunction with the fixed radius of pin 34 relative to pivot enables said tilting of supporting member 20. The difference in radial distance of each of pivots 30 and 22-24 relative to pin 34, taken in conjunction with said movement of pin 34 in slot 36,- enables'a relatively small rotation of supporting member 20 in response to a relatively large rotation of lever handle 28a. As shown, the extremities of slot 38 define the limits of rotation of supporting member 20, although it will beapparent that other limit stop means could readily be provided for the purpose.

A pper housing 46 (Figs. 1, 2, 3 and 4) comprises preferably unitary side, rear and partial frontal wall portions, an qpen'bottom, and an aperture 48 formed in its upper extremities, said aperture having light-shielded louvers 49 mounted therewithin. I Housing 46 serves to substantiallyenclose elements of the apparatus, presently to be described, and is pivotally mounted upon supporting member 20 by hinge means 50. Suitable latching means, such as latch 52 (Fig. 4) which is adapted to be inserted in a perforation 54 formed in an inner portion of the projector, is provided for holdinghousing 46 at closed position When housing 46 is pivoted about hinge 50 to its open position, access may be had to elements normally enclosed thereby.

A plate, member 56' (Figs. 3- and 4), having a circular aperture '58 formed therein, is rigidly attached to frontal portions ofsupporting member 20, the rigidity thereof being enhanced by a A pair of l As shown in Figs. 4

4 supporting strut 59 (Fig. 4). A frontal housing 60 is rotatably mounted upon plate member 56, mounting means therefor being shown in Figs. 3, 4, and 11, and comprising a circular plate 62 rigidly attached, as by welding, to a rear wall portion 60a of housing 60. Plate 62 has a projection aperture 63 and a plurality of threaded perforations 64 (Fig. 3) formed therein. Rear wall portion God has a projection aperture 65 formed therein. Peripheral portions 62a of said I plate are adapted to be slidably inserted in aperture 58 of plate member 56. An annular springlike washer 66, of larger outside diameter and smaller inside diameter than circular aperture 58 of platemember 56, and having bearing surfaces 65a. and a plurality of perforations 68, like in number and relative position to perforations 64 of plate 62, is mounted upon plate 62 by a screen, may beelevated or lowered with respect plurality of screws 10 (Figs. 3 and 4) extending through perforations 68 and engaging threaded perforations 64. When screws, 10 are tightened, bias is applied by washer 66 to said screws sum:

. cient to draw housing portions fifla. in positive but rotatable contact with plate 56. Housing 60 may thereby be readily rotated with respect to plate member 56, rear wall portion 60a preferably being formed to extend slightly beyond other rear wall portions of housing 60 to provide a reduced bearing surface for the purpose.

Frontal housing 60 has a plurality of apertures formed in side, upper and lower portions thereof as shown in Figs. 1, 2, 3 and 4. Slot-like apertures 12' (Figs. 1 and 3) are adapted to have a slide carrier inserted therein. Light-shielded apertures or louvers 14 (Figs. 1 and 3) serve as ventilating means for said housing. Apertures 16 and 78 (Figs. 3 and 4) are adapted to have mechanism 80 (Figs. 1, 11 and 13), for supplying and advancing a slide film, mounted therein. Aperture 1 8 also serves to admit cool air to housing 60, as will presently be described. As shownv in Figs, 2, 3. and 4, a cover; plate 8! having lightshielded apertures 82 formed therein, provides a, closure for aperture 16 when slide film mechanism 80 is removed from housing 60, cover plate 8| being releasably held at operative position by barrels which mount objective lenses of variousfocal length for use withslides of differentv types.

Referring to'Fig. 3, line A-A represents an optical axis extending through-opticalelements of the projector, presently to be described. A forward prolongation of said opticalaxis as, for example, an extension thereof to a projection to said screen through previously described tilting mechanism of the projector. I lever handle 38a of the tilting mechanism, as viewed in Fig. l, is manuallyv rotated. in a counterclockwise direction, pin 34 is caused to' travel; alongslot '36, 'while providing a bias against slot surface 36a, and to, cause. pivotal movement of supporting member 20 in a counter-- clockwise direction around pivotal means 22 24".

Thus, when Accordingly, upper housing46, frontal housing 60, -a dapter 86 and lens-barrel 88, and elements mounted therewithin, .willsimultaneously undergoarcuate or bodily movement in asimilardirection and said extension of optical axis A will be elevated with respect to thezprojection screen.

A clockwise rotation of lever handle 28a will pro-,.

duce a reversal of the aforesaidmovements.

Elements mounted within housing 46, which areillustrated in assembled relation in Figs.,. 3'

and 4-, include a spherical-concave reflector 94, a prefocused filament lamp 85, having a filament 96, the base 91 of which is adapted to bemounted in socket 98, and acondenser lens systemIDlL.

Thelatter, in a preferred embodiment, comprises aspherie lens elementsI02 and I04having heat shield I06 interposed therebetween. Said lens and heat shield elements may appropriately beef molded construction, having flanged edges I02a, I04a and I06a, respectively, for mounting the Condenser-lens system I shown inqfurther.

detail in'Figs. 8, 9, and 10, is'mountedin a' carriage I08. The latter, ,in .turn is releasably mounted between track members IIO. and-II2 (Figs. 1, 3 and 4) which are rigidly attached to a. pair of baffles; H4 and H6 extending inwardly from frontal plate member156 .and supportedby flange 20b of supportingmember 20. .Strut59 is rigidly attached to bafiles H4 and" IIS- and to. plate member 56. and provides a relative rigidity.

of (said elements.

;.Conden ser lens carriage. I08 (Figs. 8, 9 and 10) includes various components which will now be described. A preferably .metallic plate-like frame-II8 comprisinggvertical flange portions H811, and a circular aperture I20,,formed-therein provides a principal support. .Aplurality ofexcised areas I20a are formed in frame II8 to ex,. tend radially outwardly from said aperture I20; A rimmedretaining ring.. I22, comprising a plurality of tabs Ina-extending inwardly therefrom, is employed to encircle and bear against the flangeIIlEa (Fig. 3) of said heat shield, tabs 'I22a being inserted in excised areas I20a and bent. radially outwardly against frame -,II8. A frame I24, generally similar to frame I I8, comprising vertical flange. portions. I 2411, acircular aperture I26 (Fig. 3) forn 1ed therein, and arplurality of excised areas similar to those of frame S -extending outwardly from said aperture is employed for mounting aspheric lensl02, Lens III-2 is, mounted within aperture I26, rimmed retaming ring I28,gener'ally similar to ring I22, placed against lens flange H121: and tabs I28a thereof" are insertedin said excisedareas and I24.

bent radially outwardly against frame q Aspheric lens I04 islmounted in frame I30 com,-

prising vertical flange portions I 30a, a circular.

aperture I32 formed therein, and a plurality of excised areas similar to thosepreviously described extendingoutwardly from said aperture. Lens suitable concavlties I (Fig. 9) formed inthe side flanges I24a of frame I24. Frame I30is similarly mounted between opposite extremitiesof said cross arms by a pair of bosses I52 and I54 and a second pair of bosses I58 and I58 which are adapted to engage concavities similar to con- I04 is'inserted injaperture I32, rimmed retaining ring: I34 is placed against lens flange I04a, and the tabs I34a thereof are inserted in said excised areas 'and bent against frame I30. I A plurality of spring-like cross arms I36, I38, I40 and I42 (Figs. 3, 4, 8 and 9) are rigidly mounted upon upper and lower side portions of frame II8. Frame I24'is pivotally mounted between given extremities of the cross arms by a pair of pivotal bosses I44 and I46 (Figs. 3 and 8) formed in cross arms I38 and I42, and is held at operative position-by a pair of detent bosses I48 and 'l50 (Figs. 3 and 8) formed in cross arms I86 and I40, said bosses being adapted to engage cavity. I5I.. A plurality of outwardly. extending rigid. ears or lugs I60, I62, I64'and I66 are pref-.

erably formed toexten-d from portions ofj-the crossarms so as to be predeterminedly vertically, positioned.withrespect to side portionsof frame I I8. Said lugs are adapted to be slidablymounted within vertically extendingtrack means III);

and, H2 for releasably mounting the entire lens carriage, I08 in the projector. It will be notedin Fig. 10 that lug IE6 is positioned vertically down-v ward of lug I64. Track II2, comprising limit stop II2a. (Figs. 1 and 4) extends downwardly, to,a greaterfdepth than track III), comprising. limit stop IIOa. Accordingly, lens; carriage, I08: can be fully mounted in the tracks onlyiwhen lug I66 and lug I64 are inserted in track '-I I2pand.

lugsI68 and I62 are inserted in track IIO, thus insuring that'the lens assembly is always cor-,- rectly mounted, namely that the elements, are. relatively positioned in the projector as shown in Fig. 3. A handle I68 mounted on frame (I I8 is provided for rea-dilymounting orv rem'oving lens carriage I08. from the projector, frames I24 and I30 may be pivoted to open position by springing theextrem'a ities. I36a, and MM (Fig. 9) of the cross-arms apart, and the surfaces of lens elements I02, I04 and I06 may, for example, be examined and cleaned. Asphericlenses I02 and I04 may if desired, be removed entirely from carriage I I08 bythen springing apart the extremities Ofj'prOSS'fl.

arms I38 and I42. Because of their shape and interlocking relation, element I02 and I06 of the condenser lens system could-not be individually removed in a vertical direction. Pivotalmount ing of the elements avoids such a-nece-ssity- It willbe apparent that constructions of the invention which permit removal of the entire condenser lens assembly as a unit, also substantially eliminate the possibility of scratching the-ele ments or of relatively mispositioning individual elements during replacement. Above-described. means for mounting the condenser lens elements, in carriage I 08, and for mounting said carriage i tr'ackmeans H0 and H2 comprise a plurality of contacting surfaces so relatively positioned as to insure that the optical axis of the condenser lens system "extends centrally, respectively, throughapertur'e 58 of plate member 56, aperture 63 of housing 60, the aperture of adapterand lens barrel 92 and through objective lens ele-.

ments which, although not shown, are understood to be mounted in the latter. f

Lamp socket 98, as shown in Fig. 3, is adjustably and releasably mounted upon flange portion 20b of supporting member 20' as, for example, in

a clamp I'I0 carried by the flange portion 20b.

'I h'e clamp I18 is secured to the portion 20b by .a pair of wing members I12 which are rigidly at-J tached to said clampand extend laterally therefrom, each of said members 112 having a perror' tion I14 (Fig. 4 formed therein adjacent its extremityu Screw means I16 (Figs. 4'and 5) are inserted through perforations I14 and engaged in threaded perforationsII8 (Fig. 4) formed flange portion 20b," said screws being of appre ciably smaller diameter than perforations II4. When screw means IIB are loosen-ed,.clamp I10 maybe adjusted in aplurality of directions as permitted by the difference in diameters'of the When the lens carriage is removed,

screws and perforations. A tensioning screw I80 (Fig. 3) engaging a nut (not shown) may be loosened to permit vertical or rotational adjustment of socket 98 in clamp H9, or to permit its removal therefrom.

A second clamp I02 is releasably attached to socket 98, being held in fixed engagement therewitli'by a tensioning screw I84 (Figs. 3 and 4) which is threaded in a nut I86. A lamp shield and heat bafiie I89 is rigidly attached'to clamp I82 by supporting studs I90, a rear wall portion of said lamp shield having a circular aperture I92 formed therein. Spherical concavereflector 94 is mounted adjacent aperture I92, the latter enabling portions of the reflector to extend there through in spaced relation to said rear wall portion of the lamp shield. Reflector 94 is rigidly mounted in a circularly apertured frame I94, the center of the reflector and the center of thecircular aperture thereby coinciding, said reflector being retained in the frame by a plurality of clips I95 (Fig. 6). Frame I94 comprises three reinforced portions I94a, I94?) and -I94c which have threaded perforations I96, I98 and 200 formed therein. perforations I90 and 200 lie on a transverse line passing through the center of the frame apertureand, accordingly, are diametrically opposite one another, and the center of perforation I98 lies on'a radial line extending from the center of theaperture at 90 to said line cutting perforations I96 and 200. Three tensioning screws 202, 204 and 208, are mounted for free rotation through suitably positioned perforations formed in the rear wall of lamp shield I88, and are somewhat loosely engaged in threaded perforations I96, I98 and 200 of the reflector frame. Coil springs 208, 2I0 and a spring (not shown), or other suitable resilient means, are respectively mounted upon tensioning screws 202, 204 and 206, on portions of the same which extend between the rear wall portion of the lamp shield and reflector mounting frame I94, said springs serving to bias reflector frame I94 in a direction away from lamp shield I88, said bias being p posed by the tensioning screws.

Referring to'Figs. 3, 6, and 7 and considering the biasing effect of said springs and said loose engagement of the tensioning screws, it will be understood that adjustment of tensioning screw 206, associated with perforation I99, provides pivotal movement of reflector frame I94 around an axis passing through perforations I98 and An adjustment of tensioning screw 204,

200. associated with perforation 200, provides pivotal movement of said reflector frame around an axis passing through perforations I96 and I98. It follows, that an adjustment of tensioning screw 202, associated with perforation I99, provides pivotal movement of the reflector frame around an axis passing through perforations I96 and 200. Said operations enable angular adjustments of the reflector 94 in accordance with said pivotal movements of reflector frame I94. A similar adjustment of all of the tensioning screws providesforward or rearward. adjustment of the reflector.

A complete positioning procedurefor lamp .95 and reflector 94 utilizing the. above-described construction follows, it being assumed for purposes of illustration, that lamp95 and reflector 94 are only approximately positioned in the projector. Assuming the condenser lenscarriage to bemounted, as shown in Fig. 3, optical axis A--A represents the optical axis of the'condenser lens The centers of I system and A indicates-the position of the focalplane of the condenser lens'system with respect to optical axis A--A. With housing 48 pivoted to open position, clamp tensioning screw I80 may be loosened thereby releasing socket 98 from clamp I70, and socket 98, lamp 95, lamp shield I88 and reflector 94 may be removed from the projector as a unit. The reflector may then be adjusted, in the manner above-described, to bring a real image of lamp filament 96 to a correct position beside the actual filament. It will be understood that clamp I82 may be released by loosening tensioning screw I84, and socket 98 rotated to obtain any prepositioning of filament 91 which may be necessary. The unit may then be remounted in the projector by placing lamp socket 98 in clamp I10 and, after adjusting said socket vertically to position lamp filament 96 at the proper height with respect to optional axis A-A, tensioning screw I80 may be tightened. Screws I16, holding the Wings of the lower clamp, may then be loosenedand the entire unit may be adjusted in any lateral directions which may be necessary to establish filament 9I correctly within said focal plane A.

A preferred embodiment of the projector is adapted to use both slides and slide film interchangeably. Mechanism 80 for handling slide film is releasably mounted'in housing as shown in Figs. land 2. In Fig. 3; the projector is shown with mechanism 89- removed, apertures 12' being adapted for introduction of a suitable slide carrier, it being understood that guide and framing means (not shown), for said slide carrier are mounted within housing 90 between said apertures I2. As shown inFig. 11, individual mounting means I2 and 23 2 are provided for positioning a slide and slide-film, respectively, in sepa-- rate planes for projection. Said mounting means are placed in spaced'relation along the optical axis and permit alternate projection of a slide and slide film as well as continuous projection of one or the other form of transparency.

The slide film advancing mechanism (Figs. 1, 11,12 and 13), comprises a supporting bracket 2I'4 which is detachably mounted upon a supporting member 2'IB, carried'byh0using 60, by screw means 2I-8 (one screw and member'not shown), said screw 'means being accessible through aperture 13' (Fig. 3). Bracket 2I4' such as 35 mm. slide film, and a pair of actuating knobs 223 positioned at each extremity of the shaft, for rotating said sprocket means. Suitable rotatable detent means 224 (Fig. '13), mounted upon shaft 220 and engaging fixed spring-like detent' means 225 are provided for pcsitioning frames of film at the, projection aperture. Frictional framing means 229 for, rotating said knobs, sprocket and detent means to gether, as a unit,. to initially position the ,fllm are also provided, said framing means being actuated by lever 221.

Means associated, with the film advancing,

mechanism for supplying the slide. film comprise an open magazine 228 having a spring-actuated plunger 229 mounted, upon a. wall thereof. Said plunger may be drawn outwardly from magazine 228., against the bias of spring 230. A roll of slide film may then be placed in the magazine, and the plunger allowed to return to its normal position through the open center of the film roll, this releasablyholding the film inthe magazine.

Magazine 228, as shown in Figs. 11, 12, and.

peripheral portions of sprocket 222.

accommodate either type of film. which illustrates both a surface of guide plate 13, is'formed substantially unitarywith composite plate means 232, the latter including or having associated therewith components for guiding the film to projection apertures, presently to be described, for framing the film with respect to said apertures, and for guiding the fihn to said sprocket means 222. When cover "plate 8| (Fig. 3) has been removed, said unitary gaging portion '84 of the housing and an extremity 232a of the plate means bearing against A pair of slots 236 formed in the plate means permits unrestricted passage of the sprocket teeth therethrough.

'As shown in Fig. 12, plate 232 comprises channeled or track means 238 for bearing marginal portions of the film, a recessed central area 240 for avoiding frictional contact with image areas of the film, a spring-like, pressure plate 242 h'aving-an aperture 244 formed therein and comprisjection aperture 250 which is formed in plate 232.

The focal plane of an objective lens is to be established at said aperture. Means forming a third aperture 252, presently to be described, is visible in Fig; 12, looking'through aperture 250. Aperture 252 is dimensioned according to the dimensions of a single frame of film, while aperture 250 is of the size of double frames of film, said apertures being selectively adaptedto In Fig. 13,

'ection beam, aperture 25D, ,which, as above stated, 'is' formed in guide plate means 232 serves to frame an area of the film equal to two single frames thereof. Either of said framing aperlture's may be employed at will according to the requirements of the film. Where the images are printed sideways of the film, housing )6! may be rotated, as previously described, to properly position the projected images on the screen.

'I'heaforesaid constructions as shown and described permit a maximum of air circulation to all surfaces of the'elements. A blower fan 258 (Fig. 3) ,driven'by a'motor 260 is mounted within the chamber of base 12, as shown in Fig. 3 and provides a forced flow of cool air to said surfaces. Air is drawn into said chamber through apertures l6 and is expelled upwardly through aperture l8 and through a plurality of apertures 252' (FigsL'B and 4) formed in an upper frontal wall 12b of base l2.

A plurality of apertures 263 are provided in the slide supporting frame for-cooling a slide when mounted in apertures 12. The portion of cool air which is expelled through aperture l8 of base member l2 passes through supporting member 20 and is introduced to. surfaces of an inner heat bailie 2645(Figs. 3

and 4) attached to housing 46, to lamp shield I88, reflector 94, lamp 95, condenser lenses I02 and H34 and heat shield I06. Heated air is expelled between light-shielded louvers 49 and through aperture 48 at the top of the projector. The tapered upper contour of housing 45 adjacent aperture .48 thereof, contributes to said expulsion of air in the form of a relatively narrow column which results in an upward flow of air adjacent outer wall surfaces of housing 46 and thus facilitates cooling of said surfaces. The portion of cool air which is expelled through apertures 262 of base member l2 flows upwardly, substantially in the form of a column, and enters aperture 18 of housing 60 wherein it is introduced to surfaces of either a slide or a slidefilm, according to which form of transparency may be mounted therein for projection. Air is released from housing '60 through light-shielded apertures i4 and 32 and between portions of slide aperture 12 and aperture 16,- according to the type of transparency being projected. The above-described air-circulating system comprising said fan, plurality of heat bafiles, mounting means for the various elements, and plurality of air intake and outlet apertures enables maintenance of enclosed elements of relatively low temperatures during operation of the projector and also prevents external housing surfaces from becoming noticeably heated.

Take-up means 266 is provided for receiving the slide film after its projection'and for maintaining said film in a coiled condition ready for rewinding. Said take-up means may preferably be of a U shape and have a transverse portion 2661i adapted-to have the film coiled therearound and other portions adapted tobe releasably attached'to housing 60 such as a pair of clip-like members 236a. When a strip of slidefilm is advanced from sprocket 222 it has an inherent tendency to coil upon. itself. Take-up portion 266!) is positioned so that a coil of slide film will be formed thereabout after leaving sprockets 222. As the bulk and Weight of the'film increases it is supported by member 2661). When all of the film has passed to the take-up means, the trailing edg thereof may be drawn from the coil and the film may be rewound upon itself for placing the same in suitable condition for further projection.

It will be apparent that certain changes in the constructions set forth could be made without departing from the spirit of the invention and, therefore, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Attention is called to the fact that structure disclosed in this application is being claimed in copending divisional application No. 276,102 which was filed March 7, 1952.

What is claimed is:

1. In a projector, a releasable substantially rectangular supporting member'for carrying both a plurality of optical elements and housing means therefor and for enabling both the tilting of said elementsand housing means to elevate or lower a projection beam and provide access within enclosed portions of the projector, said supporting member comprising an apertured upper wall, and frontal, rear and side walls depending therefrom and terminating to form a lower aperture, the depending side walls having a pair of slots extending preferably rearwardly from their frontal edges for rendering a portion of said side walls compressible, complementary boss and recess means for pivotally and releasably connecting the supporting member withv a projector base within which said member is adapted to be pivoted, one

of said complementary means being carried by housing and adjustably mounting a lamp, an op-- tical system and film accommodating means comprising a hollow base having an aperture in an upper wall thereof, an intermediate supporting member pivotally mounted upon said base, said member being substantially open at the top and bottom and having side walls depending partially within the aperture of said base, means carried by said base and intermediate supporting member for tilting the latter about a horizontal axis, housing means pivotally mounted upon said intermediate supporting member for enclosing and permitting access to said lamp and a condenser and reflector of said optical system, internal baffie means rigidly attached to said pivotal housing means, frontalplate means extending upwardly from and rigidly attached to said intermediate supporting member, said plate means abutting said pivotal housing means at closed position of the latter and havin an aperture for permitting passage of light rays emanating'from said lamp, a second internal bafile means extending inwardly from said frontal plate and abutting said first-named bafile means at closed position of said pivotal housing means, a third baffle means mounted upon said intermediate supporting member and positioned between said lamp and first-named baffle means, and frontal housing means connected to said frontal plate for mounting an objective and film aocommodating means.

3; In a projector, the combination of means for housing and adjustably mounting a lamp, an optical system and film accommodating means comprising a hollow base having an aperture in an upper wall thereof, an intermediate supporting member having a releasable pivotal connec tion at frontal portions thereof with said base, said member having an inwardly extending flange for mounting a lamp socket at its upper extremities and being substantially open at the bottom and having resilient side walls depending partially within the aperture of said base which may be compressed for releasing said pivotal connection therewith, lever, pin and slot means carried by said base and intermediate supporting member for tilting the latter about a horizontal axis extending transversely of said projector, housing means having a pivotal connection at rear portions thereof with said intermediate supporting member for enclosing and permitting access to said lamp and a condenser and reflector of said optical system, internal baffle means rigidly attached to said pivotal housing means. frontal plate means extending upwardly from and rigidly attached to said intermediate supporting member, said plate means abutting said pivotal housing means at closed position of the latter and having an aperture for permittingpassage of light rays emanating from said lamp, a second internal baffle meansextending inwardly from said frontal plate and abutting said first-named baflle means at closed position of said pivotal housing means, a third bafiie means mounted upon said intermediate supporting member and positioned between said lamp and first-named bafile means, and frontal housing means con.- nected to said frontal plate for mounting an objective and film accommodating means.

4. In a projector, the combination of means for housing, adj ustably mounting and emciently cooling a lamp, an optical system and film accommcdating means comprising a hollow base having a plurality of supporting feet, air inlet aperture means in a lower wall thereof, a relatively large access and air outlet aperture in central and rear portionsof an upper wall thereof and a relatively smaller air outlet-aperture infrontal portions of said upper wall, a motor driven blower fan mounted in said base beneath said air outlet apertures, an intermediate supporting member having a pivotal connection at frontal portions thereof with said base at a position directly above the bladesof said fan, said member being substantially open at the top and bottom for transmittal of air therethrough and having side walls depending partially within the aperture of said base. means carried by said base and intermediate supporting member for tilting the latter about a horizontal axis, lamp socket means mounted upon a flange extending inwardly from upper extremities of the side walls of said intermediate supporting member, said flange terminating to permit passage of air therebetween and circulation thereof completely around said lamp, housing means having a pivotal connection at rear portions thereof with said intermediate supporting member for enclosing and permitting access to said lamp and a condenser and reflector of said optical system, said housing means being open at the bottom and abutting said intermediate supporting member at closed position and having an air outlet aperture in an upper wall thereof, internal heat bafllle means rigidly attached to said pivotal housing means and extending around the sides and rear of said lamp, frontal plate means extending upwardly from, and rigidly attached to said intermediate supporting member, said plate means abutting said pivotal housing means at closed position of the latter and having an aperture for permitting passage of light rays emanating from said lamp, a second internal heat bafiie means extending inwardly from said frontal plate along the sides of said condenser and abutting said first-named heat baffle means at closed position of said pivotal housing means, a third heat bailie means mounted upon said lamp socket means and positioned around the sides and rear of said lamp between said lamp and first-named heat bafile means, and frontal housing means connected to said frontal plate for mounting an objective and film accommodating means, said frontal housing means having a plurality of air inlet and outlet apertures formed therein, an inlet aperture being'positioned above said relatively smaller air outlet aperture of'the base whereby air driven therethroughby said fan externally of the projector is caused to reenter the projector through said inlet aperture for cooling said filmza'ccommodating means.

5. In a projector, the combination of a hollow upper wall of said base, an intermediatesupportmg member, pivot means interconnecting said baseqand intermediate supporting member for adjustable tilting movement of the latter about a horizontally disposed axis, said intermediate supporting member being open at. the top and bottom thereof and having substantially vertical walls depending partiallywithin the aperture in said base, a housing enclosing the light source and condenser system of the projector, said housing comprising a front portion rigidly attached to and extending upwardly from said intermediate .supporting member and a rear por- .tion movably mounted relative thereto, rearwardly extending vertical flanges upon said front rear portion together with said baiile and flanges forming a second chamber outwardly of the sides and rear of said first chamber, both of said chambers being partiallyopen at the .top and bottom endsthereof so'as to, allow the passage of air therethrough, a projection aperture in said front portionjaligned with said condenser, a secondary housing carried by said front portion in alignment with said condenser and arranged to receive film supporting means, and to suDDOrt an objective outwardly thereof, and an electric motor and fan in said base beneath said pivot means and positioned so as to direct air upwardly through said chambers forcooling purposes.

, 6. In a projector, thecombination of a hollow base having a relatively large aperture in an upper wall of said base, relatively smaller aperture means in said upper wall forwardly of said large aperture, an intermediate supporting member,

pivot means interconnecting said base and intermediate supporting member for adjustable tilting movementof the latter aboutahorizontally dis 'pos'ed'axis, said intermediate supporting member being open at the top and bottom thereof and having substantially vertical walls dependingpartially within'the aperture in said base, a housing enclosing the light source and condenser system of the projector, said housing comprising a front portion rigidly attached to and extending upwardly from said intermediate supporting member and arear portion movably-mounted relative thereto, rearwardly extending vertical fl'angesupon said front portion, an internal baffle vertically disposed within and carried by said rear portion in inwardlyspaced relation thereto, said front portion including said flanges'and said internal bafiie together forming," whenfsaid rear portion is in closed position, an inner chamber for surrounding said light source and condenser, saidv rear portion together with said baflie and flanges forming a second chamber outwardly of the sides and rear of said first chamber, both of said chambers being partially open at the top and bottom ends thereof so as to allow the passage of air therethrough, a projection aperture in said front portion aligned with said condenser, a secondary housing carried by said front portion in alignment with said condenser and arranged to receive film supporting means, and to support an objective outwardly thereof, an opening in'the flower wall of said secondary housing above the smaller aperture means in said base, and an electric-motor and fan in said base beneath said pivot means and positioned so as to direct air upwardly through said chambers and secondary housing for cooling purposes. v

7. In a projector, the combination of, a hollow base having a relatively large aperturein an upper wall of said base, an intermediate supporting member, pivot means interconnecting said base and intermediate supporting member for adjustably' tilting movement of the latter about a horizontally disposed axis, said intermediate supporting member being open at the top and bottom thereof and having substantially vertical walls dependingpartially-within the aperture in said base, a housing enclosing the light source and condenser system of the-projector, said housingcomprising a front portion rigidly attached to and extending upwardly from said intermediate supporting member and a rear portion movably mounted relative thereto, rearwardly extending vertical flanges upon said front portion, an internal bafiie vertically disposed within and carriedby said rear portion in.-inwardly spaced relation thereto, said front portion including said flanges and said internal baffie together forming, when said' rear portion is in closed position, an inner chamber for surrounding said light source and condenser, vsaid rear portions together with said baffle and flanges forming a second chamber outwardly of the sides and rear of said first chamber, both of 'saidchambers being partially open at the top, and'bottom ends for the passage of air therethrough, a second baflle carried by said intermediate supporting member and disposed between said flrstmenf 8. In a projectorhaving a light source, a condensersystem, an objective and meansfor supporting film for projection purposes, the-,combination of a hollow base having an aperture in an upper wall thereof, an intermediate support ing fmember pivotally mounted upon. saidbase, said member being substantially openiat the top and bottom thereof and having sidewalls depending partially within the aperture of *said base, means carried by said base and said'intermediatesupporting member for tilting the latter about a, horizontal axis, housing means supported by'said intermediate supporting member and normally enclosing said light source and condenser, internal baiile means attached to said housing means, frontal plate means extending upwardly from and rigidly attached to "said in, jtermediate supporting member for movement therewith about said horizontal axis, said frontal platemeans substantially abutting forward portions of said housing means and having an aperture therein for permitting passage of light rays emanating from said light source, second internal baiile means carried in fixed relation to and extending longitudinally from said frontal plate means at opposite sides thereof and sub stantially abutting said first-named internal baffle means 'at locations spaced inwardly of said housing means, said housing means carrying said first-named internal baffle means being movable out of its normal position so as toprovide access to said light source and condenser system,- and supplemental housing means connected to zontal axis. 1

9. In a'projector having a light source, a condenser system, an objective and means for supporting film for projection purposes, the combination of a hollow base having an aperture in an upper wall thereof, an intermediate support- '1 ingmember pivotally mounted upon said base, said member being substantially open at the top and bottom thereof and having side walls depending partially within the aperture of said base, means carried by said base and said intermediate supporting member for tilting the latter about a horizontal axis, said tilting means comprising a manually operable lever pivotally carried by said base adjacent one of said depending side walls and at a position spaced longitudinally relative to the pivotal connection between said intermediate supporting member and said base, said lever having an actuating portion extending *from said base through a recess formed therein and a projection carried by an arm of said lever within said base, the pivotal axis of said lever being positioned adjacent said recess, a cam-surface formed on a part carried by the adjacent depending side wall of said intermediate supporting member and having slidable engagement with said projection, housing means supported by said intermediate supportin'g'member and normally enclosing said light source and condenser, internal baflle means attached to said housing means, frontal plate means extending upwardly from and rigidly attached to said intermediate supporting member formovement therewith about said horizontal axis, said frontal plate means substantially abutting forward portions of said housing means and having an aperture therein for permitting passage of light rays emanating from said light so as to provide access to said light source and condenser system, and supplemental housing means connected to said frontal plate means in vertically spaced relation to said base and supporting said objective and said film supporting 'means for movement with said frontal plate means about said horizontal axis.

10. In a projector having a light source, a

condenser system, an objective and means for supporting film for projection purposes, the combination of a hollow base having an aperture in an upper wall thereof, an intermediate supporting member pivotally mounted upon said base, said member being substantially open at the top and bottom thereof and having vertical side walls depending partially within the aperture of said base, means carried by said base and said intermediate supporting member for tilting the latter about a horizontal axis, said tilting means comprising a manually operable lever pivotally carfired by said base at a position spaced longitudinally relative to the pivotal connection between 'said intermediate supporting member and said base, a projection carried by a portion of said lever located within said base and adjacent one of'said depending vertical side walls of said inter- Ill mediate supporting member, a cam surface formed on a part carried by the adjacent vertical side wall of said intermediate supporting member and having slidable engagement with said projection so as to be elevated or lowered thereby when said projection is swung in a vertical are by movement of said lever, housing means supported by'said intermediate supporting member and normally enclosing said light source and condenser, internal bafiie means attached to said housing means, frontal plate means extending upwardly'from and rigidly attached to said intermediate supporting member for movement therewith about said horizontal axis, said frontal plate means substantially abutting forward portions of said housing means and having an. aperture therein for permitting passage of light rays emanating from said light source, second internal baffle means carried in fixed relation to and extending longitudinally from 7, said frontal plate means at opposite sides thereof and substantially abutting said first-named internal baflie means at locations spaced inwardly of said housing means, said housing means carrying said first-named internal baflie means being movable out of its normal position so as to provide access to said light source and condenser system, and supplemental housing means connected to said frontal plate means in vertically spaced relation to said base and supporting said objective and said film supporting means for movement with said frontal plate means about said horizontal axis. a

ll. In a projector having a light source, a condenser system, an objective and means for supporting film for projection purposes, the combination of a hollow base having an aperture in an upper wall thereof, an intermediate supporting member pivotally mounted upon said base, said member being substantially open at the top and bottom thereof and having side Walls depending partially within the aperture of said base, means carried by said base and said intermediate supporting member fortilting the latter about a horizontal axis, housingrmeans supported by said intermediate supporting member and normally enclosing said light source and condenser, internal bafile means attached to said housing means, frontal plate means extending upwardly from and rigidly attached to said intermediate supporting member for movement therewith about said horizontal axis, said tilting means comprising a manually operable lever pivotally carried by said base at a'position spaced longitudinally relative to the pivotal connection between said intermediate supporting member and said base, a projection carried by said lever, a cam surface formed on a part carried by one of said depending side walls of said intermediate supporting member and having slidable engagement with said projection, said lever and cam surface being so arranged that the rate of pivotal movement of said lever materially exceeds the rate of pivotal movement of said intermediate supporting member, said frontal plate means substantially abutting forward portions of said housing means and having an aperture therein for permitting passage of light rays emanating from said light source, second internal baiile means carried in fixed relation to and extending longitudinally from said frontal plate means at opposite sides thereof and substantially abutting said firstnamed internal baffle means at locations spaced inwardly of said housing means, said housing f'm'eansabout said horizontal axis.

means carrying said first-named internal baifie 12. 'In' a' projector having a light condensersystem, an objective and means for "suppemng film for projection purposes, 'thecombination of a hollow base having an aperture in an upper wall thereoffan intermediate supporting member pivotallymounted upon saidw.

base, said member 'being' substantially open at the top and bottom thereof and having side walls depending partially withinthe aperture of 7 said base, means carried by saidbase and said intermediate supporting member for tilting the latter about a horizontal axis, housing means supported by said intermediate supporting member and normally enclosing said light source and condenser, internal baffle means attached to said housing means, frontal plate means extending upwardly from and rigidly attached to said intermediate supporting member for movement therewith about said horizontal axis, said tilting means comprising a manually operable lever pivotally carried by said base at a position spaced longitudinally relative to the pivotal connection between said intermediate supporting member and said base, a projection carried by said lever, a

' cam surface formed on a part carried by one of said depending side walls of said intermediate mediate said base and said intermediate support-- ing members preventing undesired movement of the latter relative to the former but allowing easy manual actuation of said lever for tilting said intermediate supporting member, said frontal plate means substantially abutting forward portions of said housing means and having an aperture therein for permitting passage of light rays emanating from said light source, second internal bafile means carried in fixed relation to and extending longitudinally from said frontal plate means at opposite sides thereof and substantially abutting said first-named internal bafl'le means at locations spaced inwardly of saidhousing means, said housing means carrying said firstnamed internal bafile means being movable out of its normal position so as to provide access to said light source and condenser system, and supplemental housing means connected to said frontal plate means in vertically spaced relation to said base and supporting said objective and said film supporting means for movement with said frontal plate means about said horizontal axis.

13. In a projector having a light source, a condenser system, an objective and means for supporting film for projection purposes, the combination of a hollow base having a relatively large aperture in an upper wallthereof and smaller aperture means in said upper wall forwardly thereof, an intermediate supporting member pivotally mounted upon said base, said member being substantially open at the top and bottom thereof and having side walls depending partially source, a

1 within the aperture-of said base, means carried by said .base and said intermediate supporting member for tiltingthe latter about a horizontal axis disposed adjacent a forward portion of said supporting member, housing means supported by said intermediate supporting member and normally enclosing said light source and condenser, internal baffle means attached to said housing means, frontal plate meanssextendingv upwardly from and rigidly attachedto said intermediate supporting member for movement therewith about said horizontal axis, said frontal plate means substantially abutting forward portions of said houser -means and having an aperture therein for permitting passage of lightrays emanatingfrom 'said' light source, second internal ba file' means carried in fixed relation to and extending longitudinall-y from said frontal platerneans at opposite sides thereof and substantially abutting said firstnamed internal baflie meansat locations spaced "inwardly ofsaid housing means, said' housing means carrying said first-named internal baflle means being movable out of its normal position so as to provide access to said light source and condenser system, and supplemental housing means connected to said frontal plate means in vertically spaced relation to said base and supporting said objective and said film supporting means for movement with said frontal plate means about said horizontal axis, aperture means in said supplemental housing means disposed substantially vertically above said smaller aperture means in said base, and air circulating means within said base and beneath said large and smaller aperture means and arranged to direct ir upwardly therethrough for cooling thespaces within said housing and said bafile means and surrounding said light source and condenser system and the space within said supplemental housing means and adjacent said film supporting means.

14. In a projector having a lamp, a condenser, an objective and film positioning means, the combination of a hollow base having an aperture in an upper wall thereof, an intermediate supporting member having releasable pivotal connections adjacent frontal portions thereof with said base, said intermediate supporting member having an inwardly extending flange for mounting a lamp socket adjacent its upper extremities, said member also being substantially open at the top and bottom thereof and having resilient side wall portions depending partially within said aperture and which may be compressed for releasing said pivotal connection with said base, lever means carried by said base and intermediate supporting member for tilting the latter about a horizontal axis extending transversely of said projector and through said releasable pivot connections, housing means carried by said intermediate supporting member for enclosing said lamp and said condenser, internal bafile means rigidly attached to said housing means, frontal plate means extending upwardly from and rigidly attached to 

